/*
 * Copyright (c) 2007 innoSysTec (R) GmbH, Germany. All rights reserved.
 * Original author: Edmund Wagner
 * Creation date: 22.05.2007
 *
 * Source: $HeadURL$
 * Last changed: $LastChangedDate$
 * 
 * 
 * the unrar licence applies to all junrar source and binary distributions 
 * you are not allowed to use this source to re-create the RAR compression algorithm
 *
 * Here some html entities which can be used for escaping javadoc tags:
 * "&":  "&#038;" or "&amp;"
 * "<":  "&#060;" or "&lt;"
 * ">":  "&#062;" or "&gt;"
 * "@":  "&#064;" 
 */
package de.innosystec.unrar.rarfile;

import de.innosystec.unrar.io.Raw;

/**
 * The main header of an rar archive. holds information concerning the whole
 * archive (solid, encrypted etc).
 * 
 * @author $LastChangedBy$
 * @version $LastChangedRevision$
 */
public class MainHeader extends BaseBlock {
	public static final short mainHeaderSizeWithEnc = 7;
	public static final short mainHeaderSize = 6;
	private short highPosAv;
	private int posAv;
	private byte encryptVersion;

	public MainHeader(BaseBlock bb, byte[] mainHeader) {
		super(bb);
		int pos = 0;
		highPosAv = Raw.readShortLittleEndian(mainHeader, pos);
		pos += 2;
		posAv = Raw.readIntLittleEndian(mainHeader, pos);
		pos += 4;

		if (hasEncryptVersion()) {
			encryptVersion |= mainHeader[pos] & 0xff;
		}
	}

	/**
	 * old cmt block is present
	 * 
	 * @return true if has cmt block
	 */
	public boolean hasArchCmt() {
		return (this.flags & BaseBlock.MHD_COMMENT) != 0;
	}

	/**
	 * the version the the encryption
	 * 
	 * @return
	 */
	public byte getEncryptVersion() {
		return encryptVersion;
	}

	public short getHighPosAv() {
		return highPosAv;
	}

	public int getPosAv() {
		return posAv;
	}

	/**
	 * returns whether the archive is encrypted
	 * 
	 * @return
	 */
	public boolean isEncrypted() {
		return (this.flags & BaseBlock.MHD_PASSWORD) != 0;
	}

	/**
	 * return whether the archive is a multivolume archive
	 * 
	 * @return
	 */
	public boolean isMultiVolume() {
		return (this.flags & BaseBlock.MHD_VOLUME) != 0;
	}

	/**
	 * if the archive is a multivolume archive this method returns whether this
	 * instance is the first part of the multivolume archive
	 * 
	 * @return
	 */
	public boolean isFirstVolume() {
		return (this.flags & BaseBlock.MHD_FIRSTVOLUME) != 0;
	}

	/**
	 * returns whether this archive is solid. in this case you can only extract
	 * all file at once
	 * 
	 * @return
	 */
	public boolean isSolid() {
		return (this.flags & MHD_SOLID) != 0;
	}

	public boolean isLocked() {
		return (this.flags & MHD_LOCK) != 0;
	}

	public boolean isProtected() {
		return (this.flags & MHD_PROTECT) != 0;
	}

	public boolean isAV() {
		return (this.flags & MHD_AV) != 0;
	}

	/**
	 * the numbering format a multivolume archive
	 * 
	 * @return
	 */
	public boolean isNewNumbering() {
		return (this.flags & MHD_NEWNUMBERING) != 0;
	}
}
